Project Summary The major goals of this proposal are to investigate the impact of spatial cueing on attention and perceptual processing in infancy using eye tracking and event-related potentials (ERP), and to determine areas of the brain involved in processing previously cued or uncued visual stimuli in infancy using realistic head modeling and cortical source analysis. Research has shown that utilizing spatial cues designed to elicit covert orienting (i.e., focusing attention on a spatial location without looking at it) can enhance perceptual processing and memory in infancy (e.g., Markant et al., 2015; Ross-Sheehy et al., 2011). Findings indicate that the benefits of spatial cueing on infant perceptual learning and memory occur exclusively on trials believed to elicit inhibition of return (IOR). Thus, infants may demonstrate optimal learning in conditions that require inhibitory processes. Alternatively, the effects of spatial cues on infant attention and perceptual processing are likely determined by multiple factors, including task characteristics and age, and covert orienting likely enhances attention and perceptual processing to targets regardless of whether or not inhibitory processes are engaged. Specific Aim 1 is to determine the effects of spatial cueing and covert orienting on attention and perceptual processing for 3-, 6-, and 9-month-old infants. A multilevel systems approach will be utilized to examine infants' performance on a modified spatial cueing/recognition memory task through the combined use of eye tracking and ERPs. This will allow for the most comprehensive analysis to date of potential mechanisms associated with covert orienting, visual attention, and perceptual processing in infancy. Specific Aim 2 is to determine areas of the brain involved in processing cued and uncued visual targets for 3-, 6-, and 9-month-old infants. Realistic head modeling and cortical source analysis of the ERP data will be utilized to achieve this am. It is predicted that covert orienting will enhance attention and foster perceptual processing across conditions for 6- and 9-month- old infants based on functional maturity of the frontal areas involved in attentional control and inhibitory processing. This work will fill a major gap in the existing literature regarding neural mechanisms involved in processing visual targets following covert orienting in infancy - a process that is fundamental to visual processing in cluttered naturalistic settings. Findings from the proposed research can inform future work aimed at identifying atypical patterns of visual cognitive development for children at risk for developmental disabilities.